This invention relates to rolling seats, tables and other structures, with particular utility for baby walkers. This invention specifically addresses safety brakes on such structures.
Safety brakes have been incorporated into the construction of baby walkers to permit an adult to secure such a walker in a stationary position when desired. This is useful when a child must be left unattended, even momentarily, preventing accidents which might otherwise occur.
A braking mechanism in current use is shown in Schwartz, U.S. Pat. No. 4,579,359, Apr. 1, 1986 (Dorel Co. Ltd.). This mechanism consists of a pair of U-shaped bars pivotally mounted to the base of the walker. When braking is desired, these bars are swung down below the wheels to lie flat on the floor on which the walker rests, lifting the walker frame so that the wheels are no longer in contact with the floor. When not in use, the bars are swung up through the center of the base, permitting the wheels to be returned to rolling contact with the floor. In order to reach its stable flat position on the floor, the bar must swing through an arc which requires lifting the walker by hand to provide sufficient clearance. As the drawings in the Schwartz patent indicate, a considerable amount of clearance is required, so much so that both the walker and the baby occupying it must be disturbed substantially in order to move the bar into its braking position. This is particularly inconvenient for the adult, since it requires two hands as well as reaching either far under the walker or into the center of the base frame.
Latching mechanisms have also been provided to engage such bars when in the nonbraking position. These consist of protruding knobs on either side of the base frame. The somewhat resilient U-shaped bars are forced under these knobs, and are releasable by manual pressure outward on the bars themselves. Since the knobs are needed to hold the bars up while the walker is mobile, their release requires a further motion by the operator when the operator desires to move the bars into their braking position. The operator must first force the bar around both knobs (requiring both hands), then lift the walker frame several inches off the ground, and reach through or underneath the frame to swing the braking bar into position. Aside from being a complicated movement, this seriously disrupts the equilibrium of the baby occupying the walker (and any objects placed on the walker), and is impossible for the adult who has only one hand free.
A simplified and much improved braking construction has now been developed. According to the invention, the braking bar on which the vehicle frame rests when braked is a straight bar, pivotally mounted to the vehicle for rotation through an arc. The braking position is slightly beyond the lowest point of the arc, preferably about 10.degree.-15.degree. past it. Without a U-shaped bar, no extra clearance is required for swinging the braking bar into position. The structure further includes a spring urging the bar into its braking position, and a releasable catch to engage the bar when lifted upward and out of the way to restore mobility to the walker.
In preferred embodiments, the catch is an attachment to the base of the walker, made of resilient material which can be manually pressed to release the braking bar, whereupon the spring forces the bar to pivot into the braking position. The brake is thus engaged by a simple one-hand motion.